Influence of Design Features on Underwater Towed System Stability

Abstract

Development of faired cables lias increased the feasible speed arid deptli of underwater towed systems, but a much more refined approach is now needed to obtain good dynamic stability with passively stabilized systems. Parametric analytical stability studies have demonstrated some fundamental effects of cable and body designs and their interactions on body behavior. These studies were based on a relatively simple mathematical model, which included approximate cable configuration parameters and body virtual masses and inertias. Results demonstate the existence of a mode dominated by cable configuration, a mode dependent on cablebody coupling effects, a mode primarily affected by body design and three modes unlikely to be of practical importance. Relative effects of primary cable and body design features are shown in root-locus form, and conclusions are drawn concerning their significance to the over-all system.